The metadata below describe the original scanning. Follow the "All Files: HTTP" link in the "View the book" box to the left to find XML files that contain more metadata about the original images and the derived formats (OCR results, PDF etc.). See also the What is the directory structure for the texts? FAQ for information about file content and naming conventions.
March 28, 2017 Subject:
It is unique that individuals who may not be in a position to find a copy have such a resource.
Published in 1912 is unique as it is after Special Relativity Theory and published before General Relativity Theory.